Toy vehicle

ABSTRACT

A driving motor is connected to a rear wheel side axle. A steering motor is installed at the center of the front part side of a chassis. An eccentric weight is mounted on a rotation shaft of the steering motor longitudinally along a vehicle body. A controller is used to control the rotation direction of the steering motor. When the eccentric weight rotates in one direction by power of the steering motor, front wheels move in one of the vehicle width directions, by which yaw rotation takes place on the chassis. The eccentric weight rotates reversely, by which reverse yaw rotation takes place on the chassis.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a toy vehicle which is provided with a driving device for travel and a steering device for steering the direction of movement.

The present application claims the right of priority to Japanese Patent Application No. 2010-123897 filed on May 31, 2010, in Japan, the content of which is cited herewith.

2. Description of the Related Art

A toy vehicle which is operated by radio control, and which is provided with a driving motor (driving device) for travel and a steering device is commonly known (refer to Patent Document 1, for example).

In the above-described toy vehicle, the driving motor for travel is connected to an axle of rear wheels via a gear, and left and right front wheels are steered by the steering device. In the steering device, knuckles which support the left and right front wheels so as to rotate are retained on a chassis so as to sway. And, each of the knuckles is coupled to a steering motor via a plurality of links and a rack-and-pinion mechanism. In this toy vehicle, rotation of the steering motor is controlled to freely adjust a rudder angle of the left and right front wheels.

PRIOR ART DOCUMENT Patent Document Patent Document 1: Japanese Published Patent Application, First Publication No. 2006-136704 SUMMARY OF THE INVENTION Problem to be Solved by the Invention

A conventional toy vehicle of this type has a large number of components which configure a steering device for steering left and right front wheels, and is complicated in structure. As a result, this contributes to an increase in production cost.

Further, the conventional toy vehicle causes a chassis to turn by driving the rear wheels and steering the front wheels in synchronization. That is, in order to cause a vehicle body to turn, it is necessary to steer the vehicle body, while moving the vehicle body forward and backward. This requires a turning radius which is at a substantial level. As a result, it is difficult for the conventional toy vehicle to turn in a narrow space.

An object of the present invention is to provide a toy vehicle which is smaller in turning radius than a conventional one and simple in structure.

Means for Solving the Problem

The toy vehicle of the present invention is provided with a chassis, wheels which are arranged on the left and right at the front and the rear of the chassis and pivotally supported on the chassis so as to rotate freely, and a steering device which is installed on the chassis for steering the left and right wheels at least at one of the front and the rear of the chassis. The steering device is provided with a rotation motor which is arranged at the center of the chassis in a vehicle width direction so that a rotation shaft is positioned longitudinally along a vehicle body, an eccentric weight which is mounted on the rotation shaft, and a controller which controls a rotation direction of the rotation motor. The eccentric weight is arranged at the front part or the rear part of the chassis.

The rotation motor is controlled for rotation by the controller, and the eccentric weight rotates in one direction, by which a force acting on the eccentric weight is changed at a region where the eccentric weight descends and at a region where the eccentric weight ascends. That is, a driving force of the rotation motor and gravitational force act on the eccentric weight. At the region where the eccentric weight descends, the driving force of the rotation motor acts as a component force which moves downward to the eccentric weight in a perpendicular direction. At the region where the eccentric weight ascends, the driving force of the rotation motor acts as a component force which moves upward to the eccentric weight in the perpendicular direction.

Therefore, when the eccentric weight is in a descending step, the wheels, etc., are increased in ground contact loads on a ground contact surface, thereby suppressing movement on the ground contact surface in the vehicle width direction. Further, when the eccentric weight is in an ascending step, the wheels, etc., are decreased in ground contact loads on the ground contact surface and centrifugal force acting on the eccentric weight causes movement in the vehicle width direction. As a result, the chassis yaw-rotates in one direction. Further, the rotation motor is controlled by the controller to rotate in the other direction, by which the right and left movement of the chassis become in reverse in the vehicle width direction in association with rotation of the eccentric weight. Then, the chassis yaw-rotates in the other direction.

That is, a direction at which a vertical component of inertia force acts in association with movement of the eccentric weight will mutually change depending on when the center of gravity of the eccentric weight moves downward around the rotation shaft and when it moves upward around the rotation shaft. When the center of gravity of the eccentric weight moves downward, the vertical component of inertia force acting on the eccentric weight acts on the vehicle body downward, by which the vehicle body is pressed to the ground contact surface together with the gravitational force. When the center of gravity of the eccentric weight moves upward, the vertical component of inertia force acting on the eccentric weight acts on the vehicle body upward, thereby attempting to float the vehicle body from the ground contact surface against the gravitational force.

Further, a direction at which a vehicle width direction component of centrifugal force acts in association with rotation of the eccentric weight will mutually change depending on when the center of gravity of the eccentric weight moves downward around the rotation shaft and when it moves upward around the rotation shaft.

When the center of gravity of the eccentric weight moves downward around the rotation shaft, the vehicle width direction component of the centrifugal force acting on the eccentric weight acts on the vehicle body in one of the vehicle width directions. However, at this time, the vehicle body is pressed on the ground contact surface by the inertia force acting on the eccentric weight to increase a frictional force between wheels and the ground contact surface. Therefore, the centrifugal force of the eccentric weight is not sufficient in causing the vehicle body to move in one of the vehicle width directions.

When the center of gravity of the eccentric weight moves upward around the rotation shaft, the vehicle width direction component of the centrifugal force acting on the eccentric weight acts on the vehicle body in the other of the vehicle width directions. At this time, the inertia force acting on the eccentric weight attempts to float the vehicle body from the ground contact surface against the gravitational force, thereby decreasing a frictional force between wheels and the ground contact surface. Thus, the vehicle body moves in the other of the vehicle width directions by the centrifugal force of the eccentric weight. Meanwhile, the eccentric weight is arranged at the front part or at the rear part of the chassis. Therefore, for example, where the eccentric weight is arranged at the front part of the chassis, the front part of the vehicle body is subjected to actions of the inertia force and centrifugal force resulting from rotation of the eccentric weight, moving in the other of the vehicle width directions. However, since the rear part of the vehicle body is spaced away from the eccentric weight, it is less likely to be subjected to actions of the inertia force and centrifugal force resulting from rotation of the eccentric weight. Thereby, the vehicle body turns in such a manner that the front part thereof is pointed at the other of the vehicle width directions.

In the toy vehicle of the present invention, the eccentric weight may be arranged at one of the front side and the rear side of the chassis with respect to a yaw center thereof.

Thereby, movement of the chassis in association with rotation of the eccentric weight in the vehicle width direction will take place at a position deviating from the yaw center of the chassis in the longitudinal direction.

In the toy vehicle of the present invention, the eccentric weight may be arranged near above an axis line which connects left and right wheels at one of the front and the rear of the chassis.

In the toy vehicle of the present invention, continuous tracks may be attached so as to be placed respectively over the front and rear wheels on the left side of the chassis and the front and rear wheels on the right side thereof. When the wheels are rotated by the driving device, the continuous tracks on the left and right are thereby rotated via the wheels, by which the continuous tracks allow the toy to travel.

Further, a vehicle capable of traveling by continuous tracks normally turns a vehicle body by making each of left and right continuous tracks different in rotation speed. However, in the toy vehicle of the present invention, the vehicle body is made to turn by actions of inertia force and centrifugal force resulting from rotation of the eccentric weight. Therefore, it is possible to turn the vehicle body without making the left and right continuous tracks different in rotation speed. That is, it is not necessary to control rotation speeds of the left and right continuous tracks independently.

Effects of the Invention

The toy vehicle of the present invention is able to reduce production costs by simplifying a structure of the toy vehicle and also able to give yaw rotation to the chassis by using a single steering device. Thus, the chassis can be easily turned even in a narrow space.

According to the toy vehicle of the present invention, movement of the chassis in the vehicle width direction in association with rotation of the eccentric weight takes place at a position deviating from the yaw center of the chassis in the longitudinal direction. Therefore, it is possible to cause the turning force to act on the chassis.

According to the toy vehicle of the present invention, the eccentric weight rotates near above an axis line which connects left and right wheels at one of the front and the rear of the chassis, and a change in loads associated with the rotation is efficiently transmitted to the left and right wheels at one of the front and the rear thereof. Thereby, the ground contact surfaces of the wheels, etc., are more likely to move laterally with respect to a road surface. Thus, it is possible to further improve turning performance of the chassis.

The toy vehicle of the present invention is able to turn the chassis without making the left and right continuous tracks different in rotation speed. That is, it is not necessary to control rotation speeds of the left and right continuous tracks independently.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an outside view of a remote control toy of the first embodiment of the present invention.

FIG. 2 is a top view in which a body panel is removed from the toy vehicle of the first embodiment of the present invention.

FIG. 3 is a drawing viewed from an arrow A in FIG. 2 of the toy vehicle of the first embodiment of the present invention.

FIG. 4 is a drawing which shows actuation of an eccentric weight (descending stage) and behavior of a chassis when the toy vehicle of the first embodiment of the present invention turns to the right. This drawing corresponds to FIG. 3.

FIG. 5 is a drawing which shows actuation of the eccentric weight (ascending stage) and behavior of the chassis when the toy vehicle of the first embodiment of the present invention turns to the right. This drawing corresponds to FIG. 3.

FIG. 6 is a top view in which a body panel is removed from the toy vehicle of the second embodiment of the present invention.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, each of the embodiments of the present invention will be described with reference to the drawings. Each of the embodiments to be described hereinafter will be given the same reference symbols to the same parts, with redundant description omitted. Further, in the drawings, an arrow FR indicates a front face of the toy vehicle, UP indicates upward of the toy vehicle, and L indicates leftward with respect to a direction at which the toy vehicle advances. Hereinafter, unless otherwise specified, forward and backward, upward and downward, and leftward and rightward are to be in accordance with the directions of arrows in the drawings.

First, a description will be given of the first embodiment shown in FIG. 1 to FIG. 5.

FIG. 1 is an outside view which shows a remote control toy 100 including a four-wheel toy vehicle 1 and a radio remote controller 2 (hereinafter, referred to as a remote controller 2) for operating the toy vehicle 1 by remote control.

The toy vehicle 1 is provided with a chassis 12, front and rear wheels Wf, Wr and a steering device 25. The steering device 25 is provided with a rotation motor 19, an eccentric weight 24 and a controller 21. A body panel 13 is covered over an upper part of the chassis 12 which supports front and rear axles 10, 11. The front wheels Wf, Wf and rear wheels Wr, Wr are mounted respectively on the front and rear axles 10, 11. The remote controller 2 has a transmitter (not illustrated) which is built thereinto and outputs an operation signal to the toy vehicle 1 by infrared rays or electric wave. On an outer surface thereof, installed are an operation switch 14 for forward and backward movement, an operation switch 15 for leftward and rightward steering, a switch 16 for switching a radio channel, and a charge button 17. The charge button 17 is used for charging electricity by connecting the toy vehicle 1 to the remote controller 2.

FIG. 2 is a drawing of the toy vehicle 1 as viewed from above from which the body panel 13 is removed. FIG. 3 is a drawing of the toy vehicle 1 as viewed from the front from which the body panel 13 is removed.

As shown in the above drawings, the driving motor 18 (driving device) for driving the axle 11 on the rear wheels Wr side is installed at the rear part region of the chassis 12. A steering motor 19 to be described later in detail is installed at the front part region of the chassis 12. Further, at the center region of the chassis 12 in the longitudinal direction, there are installed a receiver 20 which receives a signal sent from the remote controller 2 and a controller 21 which controls the driving motor 18 and the steering motor 19 based on a signal received by the receiver 20. Power of the driving motor 18 is transmitted to the axle 11 on the rear wheels Wr side via a reduction gear 22. Heat generated from the driving motor 18 is released via a metal plate 23.

The steering motor 19 is a rotation motor similar to the driving motor 18. The eccentric weight 24, which is large in mass and formed in the shape of a thick circular disk, is mounted on a rotation shaft 19 a of the steering motor 19, with the center of gravity thereof being away from the rotation shaft 19 a.

The steering motor 19 is installed on the center of the chassis 12 in the vehicle width direction in such a manner that the rotation shaft 19 a is positioned longitudinally along a vehicle body. The eccentric weight 24 rotates around the rotation shaft 19 a on a plane surface including the vehicle width direction and the perpendicular direction. The steering motor 19 and the eccentric weight 24 are arranged near above the axle 10 on the front wheels Wf side and also arranged forward from the yaw center Y of the chassis 12. Further, the controller 21 is used to control electricity, thus making it possible to switch a direction at which the steering motor 19 rotates.

FIG. 4 and FIG. 5 are drawings which show actuation of the eccentric weight 24 and behavior of the vehicle body of the toy vehicle 1 on turning to the right.

Hereinafter, a description will be given of motion in which the vehicle body turns by the steering device 25 used in the toy vehicle 1. Regarding the rotation direction of the rotation shaft 19 a of the steering motor 19 and that of the eccentric weight 24, a direction indicated by an arrow R in FIG. 4 and FIG. 5 is referred to as a forward rotation direction, while a direction reverse to the direction indicated by the arrow R is referred to as a reverse rotation direction, for descriptive purposes.

When the rotation shaft 19 a of the steering motor 19 rotates in the forward rotation direction and the eccentric weight 24 moves so as to turn from a maximum ascended position to a maximum descended position as shown in FIG. 4, the gravitational force and the component force of the driving force of the steering motor 19 both act on the eccentric weight 24 as a force moving downward in the perpendicular direction. On the other hand, as shown in FIG. 5, when the eccentric weight 24 moves so as to turn from the maximum descended position to the maximum ascended position, the gravitational force acts on the eccentric weight 24 downward in the perpendicular direction, and the component force of the driving force of the steering motor 19 acts as a force moving upward in the perpendicular direction.

Therefore, as shown in FIG. 4, while the eccentric weight 24 moves so as to turn from the maximum ascended position to the maximum descended position, the front wheels Wf are pressed to the ground contact surface by large loads of the gravitational force and the driving force (component force) of the steering motor 19, thereby suppressing movement of the front wheels Wf in the vehicle width direction. Therefore, during the above period, the front wheels Wf will not move leftward even if the chassis 12 is pressed to the left side in the vehicle width direction by the centrifugal force acting on the eccentric weight 24.

On the other hand, as shown in FIG. 5, while the eccentric weight 24 moves so as to turn from the maximum descended position to the maximum ascended position, the chassis 12 is pressed upward by the component force of the steering motor 19 moving in the perpendicular direction, by which the front wheels Wf are temporarily decreased in ground contact loads. Therefore, during the above period, the chassis 12 is pressed to the right side in the vehicle width direction by the centrifugal force acting on the eccentric weight 24, and the front wheels Wf move rightward.

The rightward movement of the front wheels Wf takes place around the yaw center Y of the chassis 12 as shown in FIG. 2. As a result, the chassis 12 turns rightward.

On the other hand, where the rotation shaft 19 a of the steering motor 19 and the eccentric weight 24 rotate in the reverse rotation direction, the right and the left rotation in the above-described forward rotation direction are reversed. Thereby, such an action takes place that is similar to motion in which the vehicle body turns in the forward rotation direction, and the chassis 12 turns leftward.

Functions of the steering device 25 can also be described as follows. That is, when the center of gravity of the eccentric weight 24 moves downward around the rotation shaft 19 a from the maximum ascended position to the maximum descended position, a vertical component of inertia force acting on the eccentric weight 24 acts downward on the vehicle body of the toy vehicle 1, thereby pressing the vehicle body to the ground contact surface. As shown in FIG. 5, when the center of gravity of the eccentric weight 24 moves upward from the maximum descended position to the maximum ascended position, the vertical component of inertia force acting on the eccentric weight 24 acts upward on the vehicle body, thereby attempting to lift up the vehicle body from the ground contact surface against the gravitational force.

Further, as shown in FIG. 4, when the center of gravity of the eccentric weight 24 moves downward around the rotation shaft 19 a, the vehicle width direction component of centrifugal force acting on the eccentric weight 24 acts on the vehicle body in one of the vehicle width directions (leftward). However, at this time, as described above, the vehicle body is pressed to the ground contact surface by the inertia force acting on the eccentric weight 24 to increase a frictional force between the front wheels Wf and the ground contact surface. Therefore, the centrifugal force of the eccentric weight 24 is not sufficient to cause the vehicle body to move in one of the vehicle width directions (leftward).

As shown in FIG. 5, when the center of gravity of the eccentric weight 24 moves upward around the rotation shaft 19 a, the vehicle width direction component of centrifugal force acting on the eccentric weight 24 acts on the vehicle body in the other of the vehicle width directions (rightward). At this time, the inertia force acting on the eccentric weight 24 attempts to lift up the vehicle body from the ground contact surface against the gravitational force, thereby decreasing the frictional force between the front wheels Wf and the ground contact surface. Therefore, the vehicle body moves in the other of the vehicle width directions (rightward) by the centrifugal force of the eccentric weight 24.

Since the eccentric weight 24 is arranged at the front part of the chassis 12, the front part of the vehicle body moves in the other of the vehicle width directions (rightward). However, the rear part of the vehicle body is spaced away from the eccentric weight 24 and, therefore, less likely to undergo actions of the inertia force and centrifugal force resulting from rotation of the eccentric weight 24. Thus, the vehicle body turns so as to point the front part thereof to the other of the vehicle width directions (rightward).

Rotation quantity (time) of the steering motor 19 may be controlled, where the vehicle body is adjusted for a turning quantity (turning angle). That is, while the steering motor 19 continues to rotate, the vehicle body continuously receives a force which turns the front part thereof to one of the left side and the right side. Thereby, where it is desired to turn the vehicle body greatly, the steering motor 19 may be caused to rotate for a long period of time. Where it is desired to turn the vehicle body slightly, the steering motor 19 may be caused to rotate for a short period of time. In addition, where the steering motor 19 is always constant in the number of rotations during actuation thereof, the operation switch 15 of the remote controller 2 is kept depressed, during which the steering motor 19 rotates, thereby making the vehicle body turn continuously. At a time point when the vehicle body is turned to a direction which is intended by an operator, the operation switch 15 is released. Thereby, at this time point, the rotation motor 19 stops and the vehicle body also stops turning.

As described so far, the toy vehicle 1 of the present embodiment is able to impart yaw rotation to the chassis 12 by the steering motor 19 and the eccentric weight 24 arranged at the front of the chassis 12. The toy vehicle 1 is also able to freely control a direction of the yaw rotation occurring on the chassis 12 by using the controller 21 to switch the rotation direction of the steering motor 19. Therefore, the toy vehicle 1 is able to control easily and reliably a direction at which the chassis 12 travels without using a complicated mechanism such as a link mechanism or a rack-and-pinion mechanism.

Further, the steering motor 19 of the toy vehicle 1 is a rotation motor which is similar to the driving motor 18.

Therefore, the toy vehicle 1 can be produced at a low cost. Further, the toy vehicle 1 is able to impart the yaw rotation to the chassis 12 by controlling the steering motor 19 so as to rotate forward and reversely, even where, for example, the driving motor 18 is not driven. Thus, it is possible to easily change the direction of the chassis 12 in a narrow space.

Further, in the toy vehicle 1, the eccentric weight 24 is arranged at a position deviating forward from the yaw center Y of the chassis 12. Therefore, it is possible to cause the turning force to act on the chassis 12 efficiently and reliably.

Still further, in the toy vehicle 1, the eccentric weight 24 is installed near above the axle 10 on the front wheels Wf side. Therefore, vibration from the eccentric weight 24 can be efficiently transmitted to the axle 10 on the front wheels Wf side, by which the front wheels Wf mounted at end parts of the axle 10 are easily allowed to move laterally with respect to the ground contact surface. It is, thereby, possible to further improve the turning performance of the vehicle body.

FIG. 6 is a drawing which shows the second embodiment and corresponds to FIG. 2 of the first embodiment.

The second embodiment is substantially similar in fundamental configurations of the toy vehicle to the first embodiment but different in that continuous tracks (endless tracks) 30L, 30 R are attached so as to be placed respectively over the front wheel Wf and the rear wheel Wr on the left side and the front wheel Wf and the rear wheel Wr on the right side.

In the toy vehicle of the present embodiment, the driving force of the rear wheels Wr transmitted from the driving motor 18 is equally transmitted to the left and right continuous tracks 30L, 30R. And, the ground contact surfaces of the continuous tracks 30L, 30R continuously move forward and backward, thereby causing the chassis 12 to travel forward and backward. In a toy vehicle which travels by rotation of the continuous tracks 30L, 30R, normally, each of the left and right continuous tracks 30L, 30R is made different in rotation speed to change a direction of the chassis 12. However, in the toy vehicle of the present embodiment, the steering motor 19 and the eccentric weight 24 are used to provide an intermittent force in an attempt to turn the chassis 12 in the vehicle width direction, thereby imparting yaw rotation to the chassis 12. Therefore, it is possible to easily and reliably change the direction of the chassis 12 without making each of the left and right continuous tracks 30L, 30R different in rotation speed.

Therefore, the toy vehicle of the present embodiment eliminates a necessity for having a mechanism which changes the respective rotation speeds of the left and right continuous tracks 30L, 30R for steering, thus making it possible to reduce production costs.

The present invention shall not be restricted to the above-described embodiments and may be changed in design in various ways within a scope not departing from the gist of the present invention. For example, in each of the above-described embodiments, the driving motor is connected to the rear part side axle, and the steering motor and the eccentric weight are installed at the front part side of the chassis. However, to the contrary, it is also possible that the driving motor be connected to the front part side axle, and the steering motor and the eccentric weight be installed at the rear part side of the chassis. It is also possible that the steering motor and the eccentric weight be installed at one of the front part side and the rear part side of the chassis, together with the driving motor.

INDUSTRIAL APPLICABILITY

The present invention relates to a toy vehicle which has a driving device for travel and a steering device for controlling the direction of movement. The toy vehicle of the present invention is able to reduce production costs and improve the turning performance.

DESCRIPTION OF REFERENCE SYMBOLS

-   1: toy vehicle -   10, 11: axle -   12: chassis -   18: driving motor (driving device) -   19: steering motor (rotation motor) -   19 a: rotation shaft -   21: controller -   24: eccentric weight -   25: steering device -   30L, 30R: continuous tracks 

1. A toy vehicle comprising: a chassis; wheels which are arranged on the left and right at the front and the rear of the chassis and pivotally supported on the chassis so as to rotate freely; and a steering device which is installed on the chassis for steering the left and right wheels at least at one of the front and the rear of the chassis, wherein the steering device is provided with a rotation motor which is arranged at the center of the chassis in a vehicle width direction so that a rotation shaft is positioned longitudinally along a vehicle body, an eccentric weight which is mounted on the rotation shaft, and a controller which controls a rotation direction of the rotation motor, and the eccentric weight is arranged at the front part or the rear part of the chassis.
 2. The toy vehicle according to claim 1, wherein the eccentric weight is arranged at one of the front side and the rear side of the chassis with respect to a yaw center of the chassis.
 3. The toy vehicle according to claim 1, wherein the eccentric weight is arranged near above an axis line which connects left and right wheels at one of the front and the rear of the chassis.
 4. The toy vehicle according to claim 1, wherein continuous tracks are attached so as to be placed respectively over the front and rear wheels on the left side of the chassis and the front and rear wheels on the right side of the chassis.
 5. The toy vehicle according to claim 2, wherein the eccentric weight is arranged near above an axis line which connects left and right wheels at one of the front and the rear of the chassis.
 6. The toy vehicle according to claim 2, wherein continuous tracks are attached so as to be placed respectively over the front and rear wheels on the left side of the chassis and the front and rear wheels on the right side of the chassis.
 7. The toy vehicle according to claim 3, wherein continuous tracks are attached so as to be placed respectively over the front and rear wheels on the left side of the chassis and the front and rear wheels on the right side of the chassis.
 8. The toy vehicle according to claim 5, wherein continuous tracks are attached so as to be placed respectively over the front and rear wheels on the left side of the chassis and the front and rear wheels on the right side of the chassis. 